Throttle-handle for pneumatic tools.



STATES "1'nrnn'i-A oFFIoE. I'

LEWIS n. sMrrn, 0E oLEA'N, NEW Yonx, AssIeNon or ONE-THIRD -T'o THOMAS.J.

Brees AAND` ONE-THIRD rro JUEIUS '.r. PLOESSEL, Eo'rH or OLE-AN, NEWYORK.

THEo'rrLE-:EANDLE Eon PNEMATIG Toons.' y

yTo allwhom tm/ay concern.' l,

vBe it known that I, LEWIS H. SMITH, a

citizen of the United States, residing at useful Improvements inThrottleHandles for Pneumatic Tools, of which the following is aspecification.- y

This invention relates to the throttle handles or valves employedl forcontrolling as pneumatic drills, and more particularly to handles .ofthis kind in which the valve 'is operated by a rotary sleeve `having Van0b.

lique slot which Vreceivesa pin connected with the valve.v

' 'In throttle handles as hitherto constructed when the valve isclosed-and the tool temf4 porarily laid aside, the rotary sleeve isliable -to become displacedaccidentally by ]ars r-or shocks,suiicientlyto open theA valve andactuate the tool, and when this occurs, thetool Vbeing uncontrolled, i'smoved in various directions by itsvibrations, sometimes coming in contact with attendants and inflictingse`V rious injury.

The object of my invention is the provision of a simple, reliable andinexpensive' lock for the rotary4 sleeve or equivalent valve-operatingmember of the throttle handle, which shall prevent such accidentaldisplacement of the sleeve and whichvat the same time permits readyunlocking thereof.

n the accompanying drawings, Figure 1 is a side elevation of thethrottle-handle, showing the valve-operating sleeve locked.

Fig. 2 is a similar view, showing said sleeve f unlocked. Fig. 3 isalongitudinal section' of the device, showing the" throttle valve open.Fig. 4 is a similar section, showing said valve closed. Figs. 5 and 6are transverse sections on `the 'correspondingly numbered lines inFig.3. l ,Y

Similar characters of referenceindicate corresponding parts throughoutthe several views.' l

1 indicates the tubular shell or casing of Vthe device having its Vfrontend 2 threaded to screw into a corresponding opening or.

socket of the-'drill-casing'or1other tool, not shown in thedrawings.Screwed into the opposite end Yof theshell is a nipple 3 adapt- `ingIthrottle valve 9 coperates'.

t ample shown in the drawings, the stem 10 of this valve is cylindrical4and slides lengththe supply of the motive fluid to portable vpneumatictools or motors, such for example,

` close the vthrottle-valve.

Vthe sleeve is mounted to slide lengthwise as u well as rotate on thecasing- 1, and a spring l 21 is arranged to shift the sleeve lengthwisePatented Aug. 17, 1915.

y Application IediJ'uIy 30, 1914 Serial No. 854,113. i

ed to receive a short pipe 41 upon which is secured the usualiuid-supply-hose 5 by a suitable clamp 6.I .a Y

Rigldly secured within theshell isa longiable valve-seat 8 with -which'a correspond- In theexln the construction illustrated in the drawings,the stem 1s for this purpose bored in its frontportiom as shown at 11,and provided 1n"oppos1te sides of its rear portion with `hereinaftermore fully described. This spring bears at its front end against the.

valve and atv its rear end against`an internal shoulder 111l of thenipple' 3.

Surrounding the central portion 4of the v tudinal guide tube. or bushing7 .provided at lts rear end with a conical or other suit-`A'longitudinal grooves 12 which communicate i i casing` 1 is thevalve-operating sleeve 15,

preferably knurled or roughened to afford a irm grip and provided withan oblique slot 16 which receives the head of a shifting screw or pin 17projecting from the valvestem 10. This pin "also passes throughlongitudinal slots 18 and 19 formed respectively in the bushing 7 andcasing 1..' The voblique slot 16 is provided with a locking notch orrecess 20, preferably located in its front edge, at or near its frontvorleading end, andfadapted to interlock with the pin 17 when the sleeveis turned forwardly to For this purpose,

toward the rear end of the 'handle to cause far enough to close thevalve. 'This `spring surrounds 'the easing and is housed by a coliar 22which overlaps thefront end of the sleeve and is provided at its frontend with internal ia'nge 23 ,whichabuts against a shoulder 24: of thecasing, the spring being 'interposed between said collar-flange and thefront end of the sleeve 15.

Surroundingr the vcasing and overlapplng the rear end of the sleeve is asumlar collar 25 provided at its. rear endl with an'internal' end of thecasing.

- ,The operation of the device is .as follows:

I When the valve is closed,- as shown in Fig. 4,

' strikes said pin, Y .initial or sliding movement of the sleeve,

the front spring 21 is partly compressed and the valve-shifting pin 17occupies the locksV ing notch 2O o'f the sleeve 15, the notch and pinbeing held in this interlocked position by the pressure ofsaid springagainst the front end of the sleeve. he sleeve is thus locked againstaccidental rotation and the valve is reliably held closed, avoiding allliability of injury to attendants, or others, when the tool is laid down.with the fluidpressure turned on. To open the valve, the operatorgrasps the sleeve 15 and pushes it toward the frontend ofr the handletollnlock its notchf20from the pin 17 and then turns Athe sleeveforwardly or in the direction of the arrow in Fig. 1, the valve beingfully opened when the rear end ofthe slot as-shown in Fig. 2. By thisthe front spring 21 is fully compressed, as shown in Fig. 3, andactspractically as a rigid abutment for the front end of the v, sleeve..In order to effect the necessary longltudinal movement of the valve toopen it by turning the obliquely-slotted sleeve, the latter must beheldfrom sliding in both directions during its rotatiom It is held againstforward displacementby the com pressed spring 21, and against rearwarddisplacement both. by the conical or rear spring and the fluid pressurewhen turned on, and by said rear spring alone when the ressure is turnedofi", this spring and the Ifluid pressure acting upon the sleeve throughagainst said Vwhich resist the purpose,

"d rotation nof the sleeve,

the valve, its stem 10 and the pin 17. other words,

the valvemust be opened spring and Aiiuicl pressures tendency of thefront spring to slide thefsleeve rearwardly. For this the front springis lighter or of less resistance than the 'rear spring, so as to beoverpowered by it, so long as the valve remains fully or partly open.When however, the valve closes by the backward the rear spring and theiluld pressure no longer oppose the front spring and the latter reactsand slides the sleeve rearwardly to interlock its notch with the pin 17,as above described.

, In the proper use of the throttle-handle ,i

when it 1s desired toturn oli the pressure,

the valve 9 is closed' by turning the sleeve I backward before closingthe usual stop cock (not shown).of the main or air supply line,

in order lthat thepressure against the valve will preventrearward.displacement of the sleeve, as' hereinbefore described. But, at-

ten'dants sometimes carelessly close said stop vcock before closing thethrottle-valve 9, thus turning off the air-pressure from said valve, andin the absence of the stiff rear spring there would be no resistance tothe backward displacement of the sleeve and the light front spring wouldtherefore slide the sleeve backward, opening .the valve instead ofhandle,

closing it, and holding it open. To guard against this improper'actionof the throttlethe rear or valve-closing spring is employed, which'actsas a substitute for the v Huid-pressure under these conditions andresists such longitudinal displacement of impossible for the operator toclose the valve withoutf at the same time locking it in that position,thus eectually guarding against. accidents of the character hereinbeforementioned. oWhile furnishing this safe-guard, the improvement isexceedingly simple and does not materially increase the cost of thedevice.

I claim as my invention:

1. Al throttle-handle for fluid-pressure tools, comprising a casing, athrottle-valve therein, a rotary sleeve mounted on said casing-andcapable ofsliding longitudinally thereon, said sleeve having means `foroperating said valve'by rotatlon of the sleeve,

and means for `automatically locking the y sleeve against rotation mentthereof.

2. A throttle-handle for fluid-pressure tools, comprising -a casing,

by longitudinal movesleeve slidable longitudina y on said casingy andhaving an oblique slot which engages tools, comprising a casing, athrottle-valve therein having a lshifting pin, a sleeve slot having alocking recess a throttle-valve v 'therein having a shifting in, and arotary mounted` on said casing and having an obli ue slot which engagessaid pin, 'said slot aving a lateral locking recess adaptedl tointerlockwith said pin in the closed position of. the valve, and aspring arranged to shi-ftsaid sleeve lengthwise to engage its lockingrecess with said pin. Y

4. A throttle-handle for fluid-pressure tools, comprising a casing, athrottle-valve therein having a shifting pinya 'sleeve mounted ony saidcasing, and having anxoblique slot which engages said pin, said slothaving a lateral `locking recess adapted to interlock with said pin, aspring arranged toshift said sleeve lengthwise in the proper directionto engage its locking recess with r f said pin, anda second spring ofgreater re-l sistance than the` first-named spring arranged to opposelongitudinal movement of the sleeve in the opposite direction.

,5, A throttle-handle for uid-.pressure tools, comprising a casing, a*throttle-valve therein having a shifting pin,. a sleeve mounted on saidcasing and having anoblique slot which engages said-pin, said Y slothaving alateral recess adapted to interlock with said pin, a springarrangedtoshit said sleeve lengthwise Iin the proper direction to engageits locking recess with said pin, anda second spring' of greater.resistance thanthe first-named spring bearing p against said valveandacting on the sleeve 1n opposition to said first-named spring.,

6. A throttle-handle for uidpressure tools, comprisinggvacasing,` athrottle-valve therein,` a movable sleeve mounted on said casing andoperatively connected with said valve, and collars *surrounding thecasing and overlapping the ends of the sleeve.

7 A throttle handle for` fluide pressure tools, comprising -a casing, althrottle-valve ltherein having a shifting pin, Ia rotary sleeve slidablelongitudinally on the casing and having an oblique slot which engagessaid pin,

said slot having a lateral locking recess ad'apted to interlock withsaid pin bythe longitudinal movement'of i the sleeve, a collar,surroundingthe casing and"overlapping the front end of the sleeve, and aspring housed within said collar and bearingagainst the adjacent end ofthe sleeve.

Witness 4my hand this 27th day of- July,

